[Octave-bug-tracker] [bug #49130] uint8 images are not shown correctly by imshow with gnuplot

[Dan Sebald]

Follow-up Comment #17, bug #49130 (project octave):

I'm not seeing anything hang here.  What version of gnuplot are you using?

There are some other recent changes that might have influence:

* scripts/general/inputParser.m(parse) : reset Unmatched and UsingDefaults
befor
  a new parse.

etc.

"double->uint8->double to achieve clamping of RGB values.  Keep cdata as
double"

Just noting that in one case there is:


    cdata = double (cdata);
    cdata = 255 * (cdata - clim(1)) / (clim(2)-clim(1));


and in another:


      cdata = double (cdata);
      clim = double (clim);
      cdata = 1 + fix (cmap_sz * (cdata - clim(1)) / (clim(2) - clim(1)));


for which the difference is "clim" cast to double.  It's probably a low
likelihood of someone setting the clim to uint8


>> cdata = [1 10];
>> clim = uint8([0 10]);
>> (cdata - clim(1)) / (clim(2) - clim(1))
>> class ( (cdata - clim(1)) / (clim(2) - clim(1)) )
ans = uint8
>> class (cdata)
ans = double


More importantly, is to make the two consistent.

I've tried experimenting to see if casting clim to double is necessary, but I
can seem to set(gca,'clim') to make it stick.

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